Along with the continuous advance of the “triple play”, the cable TV access network will gradually move towards the Next Generation Broadcasting (NGB) by transforming the two-way network. By the network transformation and integration, the radio and TV operator would not only be able to inherit the original video business, but also be able to provide various types of value-added services, such as data, VOIP, IPTV, VOD and network games, etc. In order to make full use of the existing coaxial resources, the broadband access technology based on the coaxial cable has become to be the preferred solution of the “two-way broadcasting network transformation”. By using the existing cable TV coaxial cable as the transmission media for transmitting the TV and the bi-directional data signals simultaneously, the difficulty and intensity of the two-way network transformation can be greatly decreased, and thus this technology can be applied to residential area, hotel, hospital, apartment house, office, etc., where has laid the cable TV coaxial network.
The existing broadband access technology based on the coaxial cable mainly comprises two types. One is the system based on Cable Modem Terminal Systems (CMTS) and Cable Modem (CM) devices which has a two-stage architecture comprising a head end and a terminal end; it uses protocol architectures such as ITU-T J.122, J.222, etc., and can realize the broadband data transmission based on Hybrid Fiber-Coaxial (HFC) network. The CMTS devices based on the protocol architecture such as IUT-T J.122, J.222 etc., are, however, normally designed for the large user units with scale of thousands of users, and thus the cost of those devices used for the user unit with generally only tens or hundreds of users is difficult to be beard by the operator. Therefore, the excessive cost of average bandwidth per user is one of the main obstacles of large-scale application of the CMTS devices. Furthermore, the mass noise of the CMTS devices located in the center computer room or the sub-center computer room under special network environment (e.g., Chinese network environment) is also an obstacle to provide high quality services. The other one is the system based on Ethernet over Coax (EoC) technology which has a two-stage architecture comprising a head end and a terminal end, and the existing numerous EoC standards comprise HomePlugAV, HomePlugBPL, HomePNA, MoCA, WIFI frequency reduction, etc., each of which has advantages and disadvantages in technology and has applied respectively in the radio and TV network to a certain degree around the country. Along with the integration of the radio and TV network, the lack of a unified EoC standard is disadvantageous to the interoperability, upgrade and maintenance of the radio and TV network as well as the healthy development of the whole industry chain. Moreover, the EoC technology also has defects in bandwidth, QoS assurance, manageability and the supported number of users.
Along with the further development of the radio and TV network integration and the large-scale operation of the three network convergence, the cable TV access network needs to satisfy the operating requirements of network compatibility, wide bandwidth service bearing, multiple-service QoS assurance, operability and manageability. In conclusion, those in the prior art can not satisfy these requirements very well.